RESUMEN
The main habitat of Eubacterium suis (E. suis) is the preputial diverticulum of male pigs. E. suis can be transmitted from boars to the vestibule of sows at the time of mating and ascending urinary tract infections in sows may result. A total of 195 swabs of the preputial diverticulum was collected for prevalence studies of E. suis infections in adult breeding males on Brazilian (n = 96 boars), Portuguese (n = 78 boars) and Argentinian (n = 21 boars) farms. The fixed smears were stored at 4 degrees C for one to four months until indirect immunofluorescence test was performed. Eubacterium suis was found in 75 (78%), 52 (67%) and 16 (76%) boars, respectively. These results indicate that E. suis is present in Brazil, Argentina as well as in Portugal and may be involved in urinary tract infections of sows more frequently as it is known till now.